U.S. patent number 10,117,500 [Application Number 13/001,727] was granted by the patent office on 2018-11-06 for makeup method and a device for implementing such a method.
This patent grant is currently assigned to L'OREAL. The grantee listed for this patent is Didier Gagnebien, Henri Samain. Invention is credited to Didier Gagnebien, Henri Samain.
United States Patent |
10,117,500 |
Samain , et al. |
November 6, 2018 |
Makeup method and a device for implementing such a method
Abstract
The present invention provides a method of making up human
keratinous material, the method comprising: taking at least two
measurements of an optical characteristic of said keratinous
material at different locations; and applying a composition to the
keratinous material, the composition modifying a characteristic of
the appearance of said keratinous material so as to give it an
optical characteristic intermediate between the measured optical
characteristics.
Inventors: |
Samain; Henri (Bievres,
FR), Gagnebien; Didier (Sceaux, FR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Samain; Henri
Gagnebien; Didier |
Bievres
Sceaux |
N/A
N/A |
FR
FR |
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Assignee: |
L'OREAL (Paris,
FR)
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Family
ID: |
40409765 |
Appl.
No.: |
13/001,727 |
Filed: |
July 10, 2009 |
PCT
Filed: |
July 10, 2009 |
PCT No.: |
PCT/IB2009/053014 |
371(c)(1),(2),(4) Date: |
February 16, 2011 |
PCT
Pub. No.: |
WO2010/004529 |
PCT
Pub. Date: |
January 14, 2010 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20110162673 A1 |
Jul 7, 2011 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61083422 |
Jul 24, 2008 |
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Foreign Application Priority Data
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Jul 10, 2008 [FR] |
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08 54710 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A45D
44/005 (20130101); A45D 2044/007 (20130101) |
Current International
Class: |
A45D
19/00 (20060101); A45D 44/00 (20060101) |
Field of
Search: |
;132/200,207,333
;600/476,310,587,317,431 ;356/425 ;607/88-89 ;424/70.1,70.51
;604/289,290 ;702/100 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101 53 249 |
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May 2003 |
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DE |
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1 210 908 |
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Jun 2002 |
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EP |
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1 298 587 |
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Apr 2003 |
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EP |
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1 310 212 |
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May 2003 |
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EP |
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1 459 782 |
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Sep 2004 |
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EP |
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2 603 183 |
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Mar 1988 |
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FR |
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2 810 761 |
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Dec 2001 |
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FR |
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2 861 883 |
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May 2005 |
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FR |
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2 343 657 |
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May 2000 |
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GB |
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A-2004-521926 |
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Jul 2004 |
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JP |
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A-2005-245521 |
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Sep 2005 |
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JP |
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A-2006-297691 |
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Nov 2006 |
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JP |
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WO 02/00189 |
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Jan 2002 |
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WO |
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WO 02/01499 |
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Jan 2002 |
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WO |
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WO 03/033270 |
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Apr 2003 |
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WO |
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WO 2004/090629 |
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Oct 2004 |
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WO |
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WO 2007/022095 |
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Feb 2007 |
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WO |
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WO 2007/056569 |
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May 2007 |
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WO |
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Other References
Apr. 15, 2014 Office Action issued in U.S. Appl. No. 13/001,671.
cited by applicant .
Jun. 13, 2013 Office Action issued in U.S. Appl. No. 13/001,720.
cited by applicant .
Dec. 24, 2013 Office Action issued in U.S. Appl. No. 13/001,671.
cited by applicant .
http://www.utexas.edu/opa/blogs/culturalcompass/2010/01/27/hair-and-makeup-
-test-photos-from-gone-with-the-wind/. cited by applicant .
Nov. 27, 2013 Office Action issued in U.S. Appl. No. 13/001,720.
cited by applicant .
Nov. 11, 2014 Japanese Office Action issued in Japanese Patent
Application No. JP-A-2011-517306. cited by applicant .
Oct. 2, 2015 Office Action issued in U.S. Appl. No. 13/001,689.
cited by applicant .
H. Katerinopoulos, Current Medicinal Chemistry, 2002, vol. 9, pp.
275-306. cited by applicant .
International Search Report issued in PCT/IB2009/053011, dated Nov.
2, 2009. cited by applicant .
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2, 2009. cited by applicant .
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30, 2009. cited by applicant .
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2, 2009. cited by applicant .
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30, 2009. cited by applicant .
Written Opinion issued in PCT/IB2009/053011, dated Nov. 2, 2009.
cited by applicant .
Written Opinion issued in PCT/IB2009/053012, dated Nov. 2, 2009.
cited by applicant .
Written Opinion issued in PCT/IB2009/053015, dated Oct. 30, 2009.
cited by applicant .
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cited by applicant .
Written Opinion issued in PCT/IB2009/053013, dated Sep. 30, 2009.
cited by applicant .
U.S. Appl. No. 13/001,720, filed Dec. 28, 2010 in the name of Henri
Samain et al. cited by applicant .
U.S. Appl. No. 13/001,671, filed Dec. 28, 2010 in the name of Henri
Samain. cited by applicant .
U.S. Appl. No. 13/001,689, filed Dec. 28, 2010 in the name of Henri
Samain. cited by applicant .
U.S. Appl. No. 13/001,688, filed Dec. 28, 2010 in the name of Henri
Samain. cited by applicant.
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Primary Examiner: Rodriguez; Cris L
Assistant Examiner: Kalach; Brianne
Attorney, Agent or Firm: Oliff PLC
Claims
The invention claimed is:
1. A method of applying make-up to a human keratinous material, the
method comprising: taking at least two measurements of a color of
the keratinous material at different location; determining an
optical characteristic forming an intermediate color and shades
thereof that are intermediate between the at least two measurements
of a color, where the intermediate color is an average or weighted
average of the at least two measurements of color of the keratinous
material; and applying a cosmetic deposit to the keratinous
material, the cosmetic deposit being the intermediate color the
cosmetic deposit being applied between at least two locations at
which the color of the keratinous material has been measured, the
color of the cosmetic deposit varying and shading off gradually
between the at least two locations where the color was measured
lying between the at least two measured colors of the keratinous
material, the color of the cosmetic deposit varying on approaching
edges of the cosmetic deposit so as to come close to the color of
the keratinous material in a vicinity of the cosmetic deposit.
2. The method according to claim 1, wherein the cosmetic deposit
includes one or more cosmetic inks.
3. The method according to claim 1, wherein the intermediate color
is an average color.
4. The method according to claim 1, wherein the measurements and
the application of the cosmetic deposit are performed by a single
handpiece.
5. The method according to claim 1, wherein the measurements are
performed at locations that are spaced apart by a distance having a
range of 5 mm to 50 mm.
6. The method according to claim 1, wherein the color of the
cosmetic deposit includes at least two different cosmetic inks.
7. A device for making up a human keratinous material, the device
comprising: an acquisition system including at least two color
sensors which are spaced apart and configured to obtain at least
two measurements of a color of the keratinous material at different
locations, a processor programmed to determine an optical
characteristic forming an intermediate color and shades thereof
that are intermediate between the at least two measurements of a
color where the intermediate color is an average or weighted
average of the at least two measurements of color of the keratinous
material; and a printer system comprising a plurality of cosmetic
inks for creating the optical characteristic; wherein the printer
system is configured to apply the cosmetic inks having the
intermediate color and shades thereof as a cosmetic deposit to the
keratinous material in an area between the different locations,
wherein the intermediate color is applied at a specific location
between the two different locations and the shades thereof vary
gradually between the intermediate color and the colors at the two
different locations the intermediate color varies on approaching
edges of the cosmetic deposit so as to come close to the color of
the keratinous material in a vicinity of the deposit, and the
device houses a handpiece that includes the acquisition system and
the printer system.
8. The device according claim 7, further comprising: an interface
enabling a user to modify the color of the cosmetic deposit prior
to printing.
9. A device for making up a human keratinous material, the device
comprising: an acquisition system enabling at least two
measurements of a color of the keratinous material to be performed
at different spaced apart locations via color sensors, a processor
programmed to determine an optical characteristic forming an
intermediate color and shades thereof that are intermediate between
the at least two measurements of a color where the intermediate
color is an average or weighted average of the at least two
measurements of color of the keratinous material; and a printer
system comprising a plurality of cosmetic inks for creating the
optical characteristic; wherein the printer system is configured to
apply the cosmetic inks having the intermediate color and shades
thereof as a cosmetic deposit to the keratinous material in an area
between the different locations, wherein the intermediate color is
applied at a specific location between the two different locations
and the shades thereof vary gradually between the intermediate
color and the colors at the two different locations the
intermediate color varies on approaching edges of the deposit so as
to come closer of the keratinous material in a vicinity of the
deposit, and the printer system includes a vibrator configured to
create a fuzziness on application.
Description
The present invention relates to making up human keratinous
material, for example the skin.
BACKGROUND
Almost everybody presents non-uniformities of color on varying
scales that relate to the face and also to the bust, the neck, the
hands, and the body as a whole.
These non-uniformities are often mere differences in color, but
they can also be associated with non-uniformities in
three-dimensional shape, e.g. recesses, dilated pores, or small
scars, because of the light and shade effects they create.
Although these color non-uniformities are well accepted by some
people, many people are ill-at-ease with all or some of the
non-uniformities presented by their skin. This is particularly true
of non-uniformities that lie on skin that can be seen, for example
the face, the hands, the bust, or the scalp.
From time immemorial, and all over the globe, compositions that
present covering power have been used to mask such
non-uniformities. By way of example, they may be in the form of a
cream or a fluid for applying by hand and in general they contain
pigments. They are applied either on the non-uniformity alone, or
over a larger area, thereby extending beyond the non-uniformity
itself.
Great progress has been made in improving such compositions, but it
nevertheless remains that they present a drawback that it is
difficult to overcome, namely since their color is predefined they
do not take account of the color of the skin.
This can raise two problems.
The first is that it is necessary to make the color of the
composition that is purchased match the color of the purchaser's
own skin. The slightest difference often produces a visible effect.
This drawback can be limited by masking the entire face with the
composition. However, under such circumstances, the face or the
body portion concerned is visibly made up, and therefore does not
look natural.
The second problem is that the color of the skin of a single body
varies considerably from one location to another. Some portions are
more pigmented, others less, some are yellower, redder, or bluer in
color. These differences are not necessarily large differences, but
the human eye is sensitive to small color differences. To be
effective, it is necessary to treat all portions of the body with
compositions of different colors. This is theoretically possible,
and sometimes even done. However such work is very time-consuming
and requires technical competence that is not compatible with
everyday application of makeup.
Publication WO 2007/022095 A1 discloses a method of applying makeup
in which an agent that modifies the reflectance of the skin is
applied to the skin by using ink jet printer technology. In one
embodiment, the device includes a scanner and an ink jet printer,
and in a single pass over the skin it analyses the skin, identifies
unattractive characteristics, calculates the improvements to be
made, and applies the agent that modifies reflectance so as to
obtain those improvements. For example, the device can give a
softer appearance to the skin by identifying pale and dark points
and by applying the reflectance-modifying agent so as to darken
pale points using a predefined averaging technique. The device may
include means for recognizing the treated zone, e.g. the cheek bone
or the cheek so that the improvements made are specific to the zone
being treated, e.g. making cheeks look rosy so as to give the
appearance of a person in better health, or darkening zones under
the cheek bones so as to make them less prominent. A colorant may
be deposited on certain portions of the skin to make it more
uniform and markers that fluoresce under ultraviolet illumination
may be used to make it easier to recognize certain regions during
treatment. In an example seeking to simulate tanning, an agent that
modifies the spectral characteristics of the skin is applied so as
to reduce contrast between pale and dark zones, darkening zones of
the skin in selective manner, while causing certain details of the
skin to disappear. In another element, pale zones around wrinkles
are darkened but the hollow zones within wrinkles are not
modified.
Publication WO 2004/090629 A2 discloses a method of printing on the
skin.
U.S. Pat. No. 6,543,893 describes an ink jet printer suitable for
being moved manually over the skin. The printer may have a screen
for displaying images that are to be printed and a device that
enables the image to be personalized, e.g. by adding text or other
information.
U.S. Pat. No. 6,622,733 describes an applicator having an ink jet
printer head.
Application US 2006/0098076 discloses a system for ink jet printing
on the skin that includes means for positioning the face. The
printer system is suitable for printing hairs on the eyebrows or
for printing color on the cheeks for blending in with a brush.
Application WO 02/01499 A2 describes a method of applying makeup by
means of a movable applicator head supported by an arm that is
articulated so as to follow the three-dimensional shape of the zone
being made up. The three-dimensional shape is acquired with the
help of one or more cameras. A design selected by the user can be
printed using an ink jet. The printing may serve to cover a pigment
mark with the same color as the surrounding skin, after performing
colorimetric analysis thereon.
Application DE 10153249 A1 describes a method of applying
compositions on the skin by means of an ink jet printing technique.
Printing may be performed using a handpiece held by the user. In a
variant, the print head may move relative to the skin by moving a
belt or a carriage on a rail that is itself movable on two
slideways at its ends.
Publication JP 2006-297691 discloses a printer system for printing
an image on the skin, the system being fitted with means that
enable the color of the skin to be measured. The printer system
takes account of the color of the skin in the image that is to be
reproduced, the print head being provided with a photodetector. For
example, for a dark skin, the quantity of ink is increased. In a
variant, not only is the lightness of the skin taken into
consideration but also its color when calculating the image for
printing.
Publication GB 2 343 657 describes a portable ink jet printer
suitable for printing a mark authorizing entry to a concert or a
discotheque on the forearm or the hand of a person. The ink that is
deposited may be visible, fluorescent, magnetic, phosphorescent, or
photochromic.
Application WO 02/00189 A1 describes a method of applying a colored
composition on the skin in which it is possible to select a blemish
on an image of the zone for treatment, which image is obtained by
means of a camera that also measures color. Image modification
software makes it possible to correct a blemish in the zone for
treatment, e.g. a depigmented zone, by outlining the zone with the
help of a computer mouse and then printing on the corrected zone
the color of the surrounding zone.
Publication WO 03/033270 discloses an ink jet printer that can be
positioned manually on the skin in order to print a tattoo.
Publication US 2007/0114305 describes an electrostatic spray device
for making up the skin.
U.S. Pat. No. 7,290,550 discloses an installation capable of
printing on the skin, in particular on the skin of the face.
Numerous appliances are also known for printing on the nails, e.g.
from U.S. Pat. Nos. 5,931,166 and 6,035,860.
None of those known printer devices is entirely satisfactory, in
particular for the purpose of obtaining makeup that is accurate,
natural, and varied.
There exists a need to benefit from novel means for making up
keratinous material, and for example hiding color or gloss
non-uniformities in a manner that is difficult to see.
SUMMARY
Examplary embodiments of the invention seek specifically to satisfy
this need and provide a method of making up human keratinous
material, for example the skin or the hair, the method comprising:
taking at least two measurements of an optical characteristic, in
particular color or gloss, of said keratinous material at different
locations; and applying a composition to the keratinous material,
the composition serving to modify a characteristic of the
appearance of said keratinous material so as to give it an optical
characteristic intermediate between the measured optical
characteristics, in particular a color or a gloss intermediate
between the measured colors or glosses.
The optical characteristic may be selected from luminance and color
or a color component, e.g. L, , or b in the Lab CIE 1976
colorimetric system.
When the measurements at said locations are the same, e.g. when the
measured colors are the same, the intermediate optical
characteristic may be identical to the measured characteristic. For
example, the deposit that is formed may have the same color.
The composition that is applied may comprise or one or more
cosmetic inks. The composition may also serve to modify skin color
or hair color by means of a chemical reaction, in particular when
the composition is selected from self-tanning agents or whitening
agents or other cosmetic compositions.
The above-mentioned reaction may be superficial.
For example, the method may include the step consisting in
automatically applying a self-tanning agent and/or one or more
cosmetic inks so as to blur the line of demarcation between a
naturally-tanned zone and a zone that has been protected from the
sun, e.g. by wearing a garment. The method may be implemented to
mask the tan lines left by a bikini top or sunglasses, for
example.
The method may be implemented on bare skin or on skin that has
already been made up.
The deposit that is formed may be of a color that is solid or
otherwise. When the deposit does not present a solid color, it
should be understood that the deposit includes at least one zone
having said intermediate color. The deposit may shade off between
two locations where the measured colors are different.
At least two, and better three, measurements of the color of the
keratinous material may be performed at different locations, and a
deposit may be formed of a cosmetic of a color that is intermediate
between the measured colors.
The deposit may be situated between locations where the
measurements were taken. This deposit may cover a skin blemish, for
example a spot, a scar, or a wrinkle, or a tan line, as mentioned
above. The deposit may be performed at equal distances from the
locations where the measurements were taken.
The measurements of color or of some other optical characteristic
may be performed simultaneously or in a short lapse of time, for
example with less than 5 minutes (min) between them.
The deposit may be formed within a short lapse of time after
measuring color or some other optical characteristic, for example
within less than 1 hour (h).
The invention makes it possible to take account of the fact that
the color of the skin of any one person varies locally. The
invention thus enables skin blemishes to be camouflaged better by
making it possible for the presence of the zone that has been made
up or treated with a self-tanning agent or a whitening agent to be
made less visible.
In an implementation of the invention, at least three measurements
are made of skin color at different locations, and cosmetic of a
color intermediate between the three measured colors is
deposited.
The intermediate color may be an average color, in particular a
color obtained by taking the arithmetic mean of each of the three
color components. The cosmetic deposit may also have a color that
varies, but that passes through at least one color that is
intermediate between the measured colors, better that is of a color
that always lies between the measured colors, i.e. having color
components that lie between the extremes of the measured
values.
Color measurement and application of the deposit may be performed
by using a single handpiece, thereby making the method easier to
implement. In a variant, the color measurements may be performed
using a single color-measurement appliance without any printer
system, which appliance is moved successively to different
locations, or by means of a plurality of color measurement probes
that are placed at said locations. The color measurement probes may
be separate from the printer system. The color measurement probes
may be fastened to the skin by using a gel, an adhesive, or a
suction cup, and they may be connected to the remainder of the
device by cables or by a wireless system. The color measurements
may be performed with the skin or the hair in contact with the
apparatus used for making the measurement. Contact makes it
possible to be independent of external lighting. Measurement
resolution may be better than 1 centimeter (cm), in at least one
direction.
Color or other optical characteristics may be measured at
respective locations that are spaced apart by distances lying in
the range 0.5 cm to 5 cm or even more.
The deposit made may be of a color, or a gloss, that varies close
to the edges of the deposit so as to come close to the color, or
the gloss, of the nearby skin. By way of example, the deposit may
have a color that varies between the locations where color was
measured, the color of the deposit approaching the respective
colors measured at each of said locations in the vicinities
thereof. This enables the deposit to blend in better with the
neighboring regions of skin or hair.
The color of the deposit may result from using at least two inks of
different colors, preferably at least three inks of different
colors, that may be mixed and/or juxtaposed on printing.
Other exemplary embodiments of the invention also provide a device
for applying makeup, the device comprising: an acquisition system
enabling at least two measurements of an optical characteristic of
keratinous material to be performed at different locations, in
particular measurements of its color; a processor unit for
calculating an optical characteristic that is intermediate between
the measured optical characteristics, in particular an intermediate
color; and a printer system (that can be any kind of deposition
system) for depositing a cosmetic that imparts said intermediate
optical characteristic by acting optically on the keratinous
material, e.g. by applying one or more cosmetic inks, or a system
for applying a composition that causes the keratinous material to
be subjected to a chemical reaction and to a change of appearance
so as to take on the intermediate optical characteristic, e.g. a
self-tanning agent or a whitening agent.
The device may be used for making up: pigment spots; age spots;
blackheads; acne; scars; stretchmarks; beauty spots; apparent
veins; wrinkles; red spots; non-uniform tanning; vitiligo;
erythrosis; rosacea; and non-uniformities of makeup (self-tanning
agent). This list is not exhaustive.
It is also possible for men to make use of the device, e.g. for
treating irregularities of skin tone, or of hair distribution.
The deposit that is formed may be of a color that is solid or
otherwise.
The acquisition system may include at least two color sensors, and
preferably at least three sensors. This enables simultaneous
measurements to be performed and/or measurements to be performed
with the device having accurate knowledge about the distances
between the sensors.
The device may include a handpiece including the acquisition system
and the printer system.
The printer system may be an ink jet or minispray system, or it may
be of some other kind.
The printer system may include a source of vibration to create a
fuzzy effect on application. When printing, the user may also move
the printer system, e.g. by moving the handpiece a little.
The printer device may include an interface enabling the user to
act, prior to printing, to modify the color of the deposit and/or
the distribution of color within the deposit.
The acquisition system may include one or more photodetectors and
lighting means of different colors. This may limit the use of
expensive components. For example, the acquisition system may have
a single photodetector placed in a measurement zone and associated
with at least three LEDs placed in such a manner as to illuminate
the measurement zone, with the LEDs being placed for example around
the observation direction of the photodetector, e.g. distributed at
equal angles. It is also possible to use a LED that is capable of
emitting as a plurality of different colors.
The acquisition system may serve to perform at least two color
measurements at different locations without moving the acquisition
system relative to the skin. The acquisition system may also
measure color at a first location and track movements over the
keratinous material to a second measurement location, e.g. by
including a movement sensor, e.g. a ball or a wheel making contact
with the keratinous material, or an optical movement sensor.
Given that the device may be connected to other apparatuses or
networks, the device may be caused to operate in a master mode (it
causes other apparatuses to capture colors, make calculations,
perform printing, and provide displays), or in a slave mode
(another apparatus causes it to perform one or more actions
selected from: capturing colors, making calculations, performing
printing, providing displays). The device may be used not only on
the skin, but also on other portions of the body, e.g. the hair or
the nails or even for treating surfaces such as fabrics, wood,
plastics materials, . . . .
Other exemplary embodiments of the invention also provide a device
for applying makeup, the device comprising a print head, e.g. an
ink jet print head, and a source of vibration to cause the print
head to vibrate during printing. The frequency vibration may lie
for example in the range 5 hertz (Hz) to 40,000 Hz. This may enable
a deposit to be made without any sharp outline, and thus for it to
be less visible.
Independently or in combination with the above, other exemplary
embodiments of the invention also provide a device for applying
makeup that includes a print head and an adjustment member enabling
the user to vary the distance between the print head and the
surface to be made up. This may serve to perform printing that is
intense to a greater or lesser extent.
The invention can be better understood on reading the following
detailed description of non-limiting implementations thereof, and
on examining the accompanying drawings, in which:
FIG. 1 is a block diagram showing various steps in an example
method of the invention;
FIG. 2 is a block diagram showing different entities in a device
made in accordance with the invention;
FIGS. 3 to 5 are diagrammatic and fragmentary perspective views
showing various examples of devices of the invention;
FIG. 6 shows an example of a color-measurement sensor; and
FIG. 7 is an electrical schematic diagram of an example of a device
made in accordance with the invention.
As shown in FIG. 1, the method of the invention may comprise a step
10 of capturing color at at least two locations on keratinous
material. This capture is performed by means of an acquisition
system 20 shown diagrammatically in FIG. 2 and described in greater
detail below.
Acquisition step 10 is followed in the example described by a step
11 of calculating a color that is intermediate between the measured
colors. This calculation is performed by a processor unit 30 that
is likewise shown diagrammatically in FIG. 2.
Step 11 may be followed by a step 12 of displaying the image or the
color that results from the calculation. This display may take
place on a screen of a user interface 40.
After the image has been displayed, an optional step 13 of the user
validating the displayed result may be necessary prior to
performing print step 14. If validation is not given in step 13,
then it is possible for the user to make a request in step 15 to
modify the result of the calculation, and then step 15 may be
followed by a new calculation.
The printing is performed with the help of a printer system 50 that
is described in detail below.
The acquisition and printer systems 20 and 50 may be grouped
together within a single handpiece 80 that is shown
diagrammatically in FIG. 3. The handpiece 80 may house the
processor unit 30. In a variant, and as shown in FIG. 4, the
handpiece 80 may be connected to the processor unit 30 over a wire
or wireless connection 85.
As shown in FIG. 5, the acquisition system 20 may also include one
or more color-measurement probes 21 that are connected via a wire
or wireless connection 85 to a handpiece 80 that houses the printer
system 50. The handpiece 80 may house the processor unit or it may
be distributed amongst the probes 21 and the handpiece. In another
variant, the handpiece 80 and/or the probe(s) 21 may communicate
with a remote processor unit. The probes 21 may be placed on the
skin for the purpose of measuring color.
Printing may be performed between at least two locations where
color has been measured. Where appropriate, a color measurement may
also be performed at a printing location and possibly also beside
it. A color measurement at the location where printing takes place
may be useful, e.g. for the purpose of verifying that the color
that results from deposition does indeed correspond to the expected
color.
The processor unit 30 may comprise a microcomputer, a minicomputer,
or any other electronic system, e.g. a programmable logic
array.
The processor unit is provided with a memory or makes use of a
memory. Any storage system is possible, for example a universal
serial bus (USB) key, a memory internal to the computer, an
electrically-programmable read-only memory (EPROM), memory cards, a
hard disk, or indeed optical storage.
The presence of a memory may enable the result of a calculation to
be printed several times over. Under such circumstances, the device
may be moved and activated for printing purposes without capturing
color again. A "reprint" button may be placed on the device, e.g.
on the handpiece, in order to make this operation easier.
The memory may be conserved after the device has been switched
off.
Provision may be made for the device to propose retaining in memory
certain colors for printing, with this being done either by access
via a menu or by having specific buttons to press. Each memory may
be associated with a computer label, thereby enabling the user to
associate a particular color with certain portions of the body, for
example.
The portion of the handpiece that is placed on the skin, also
referred to as the "contact" portion, may be plane or curved, e.g.
curved to match the shape of a portion of the face, or of the body,
e.g. a leg, an arm, a hand, the bust, the skull, . . . .
Contact surfaces are assessed in particular in the form of portions
of a cylinder or of a sphere. The shape of the contact surface may
in particular be adapted to the three-dimensional (3D) shape of the
non-plane outlines of the face or the body. Where appropriate, the
shape of the contact portion may be made to measure, after
acquiring the three-dimensional shape of the user in the region to
be treated.
The contact portion may be made out of flexible material so as to
be deformable and thus fit more closely to the shape of the region
of the body or the face on which it is placed.
The printer and/or acquisition systems may be adapted to the
non-plane shape of the treated region. For example, the print
head(s) may optionally be provided to track the non-plane shape of
the skin, and they may be provided with an option for moving,
specifically in a direction that is perpendicular to the skin.
Thus, the apparatus may include at least one print head configured
to be moved under motor drive and electronic control in a direction
that is perpendicular to the skin or other surface so as to track
the outline of said skin or surface. A distance detector and/or a
contact detector may be used to ensure that the distance between
the printer system and the skin is kept constant.
The device may contain safety systems such as a grounding contact,
a differential trip switch, a system for tripping in the event of a
hatch being opened on the base station (if any) or on the
handpiece.
The device may be provided with a warning system to indicate that
the sensors are properly positioned on the skin, in particular a
system that detects the absence of any gap, and that provides
information concerning proper positioning of the printer system on
the skin. Thus, when the handpiece is not in contact with the skin,
printing can be stopped.
The device may also calibrate colors and printing so as to optimize
accuracy. Calibration may be an automatic function. Under such
circumstances, the apparatus prints certain marks on a defined
medium, either regularly or on each occasion an ink cartridge is
changed. The apparatus may use a color sensor for determining the
color of such printing and then calculate calibration functions by
comparing the expected result with the result that is obtained.
Calibration may be refined manually, where appropriate.
A warning system may provide a warning in the event of a component
malfunctioning or an ink being used up.
The device may include a system for purging a print head after use
or for cleaning the color sensor(s), e.g. a pneumatic system.
The device may be provided with a placing detection function. This
function enables the handpiece to detect that it has been placed on
the skin. It is possible to implement this function in various
ways. For example, the handpiece may be provided with contact
detectors, e.g. based on thermal or electrical conductivity, on one
or more photoreceivers, on a pushbutton, with there being four
detectors, for example. When all of the detectors detect contact,
then the device considers that the handpiece has been put into
place.
The device may also act as an acquisition system for determining
whether it is in place on the skin. Thus, before lighting is
switched on, if the color detectors detect no light, then the
device considers that the handpiece is in place.
The device may include a visual or sound indicator to inform the
user, e.g. that capture or printing has been performed.
The device may be provided with an interface enabling information
to be sent or received, whether from a device of the same type or
from other apparatuses, via an appropriate network, the Internet,
or the telephone network.
The handpiece may optionally include an internal source of
electricity, in the form of optionally rechargeable batteries.
Once the color value has been determined, printing may take place
at different rates and also at different levels of intensity. For
example, if it is desired to print a zone having an area of about 1
cm.sup.2, then the volume of ink will typically be about 10
microliters (.mu.L).
This volume may be sent to the print head at a maximum speed in
order to finish off printing as quickly as possible. However it may
be preferred to avoid the print head working at maximum speed, so
as to enable the user to act during printing, e.g. to make a
movement or to decide to remove the apparatus before printing has
finished.
The volume may be small so as to obtain a transparency-type effect,
or conversely it may be large so as to obtain more thorough
coverage.
Acquisition System
The acquisition system includes at least one sensor for measuring
color, and that is designed to measure the color of the skin, but,
where appropriate, it may also be suitable for application to other
surfaces, e.g. to fabrics, the hair, or photographs.
Any standard for physical representation of color may be used: red,
green, blue (RGB); hue, value, chroma (HVC); Lab; cyan, magenta,
yellow, black (CMYK); reflectance curves; . . . . The choice of
standard may be pre-established in the device or left to the choice
of the user.
The spacing between the various sensors may be fixed or adjustable,
e.g. lying in the range 1 millimeter (mm) to 10 cm.
The skin may be illuminated with white light and the reflected
light may be captured by three selective detectors responsive to
red, green, and blue. In this particular setup, the acquisition
system has one or more detectors responsive to all wavelengths and
associated with specific filters.
It is possible to use a non-selective photodetector and to
illuminate using light in three colors. Under such circumstances,
use is made for example of red, green, and blue LEDs that
illuminate the skin sequentially and that enable the intensity of
the light reflected by the skin to be captured in the three colors.
The light source(s) associated with a sensor may be spaced apart
therefrom by a distance that is greater than or equal to 2 mm or 3
mm, for example.
FIG. 6 shows an arrangement comprising a photodetector 21 observing
the skin along an axis Z, together with three light sources 22,
e.g. LEDs, disposed around the axis Z, e.g. at equal angular
spacing, so as to illuminate the skin in the zone observed by the
photodetector 21.
The acquisition system advantageously includes one or more walls
constituting shields to prevent ambient light reaching the
sensor(s).
The device preferably includes at least two sensors, and better at
least three. In a particular embodiment, use is made of a linear or
matrix sensor, e.g. based on a charge-coupled device (CCD), or a
complementary metal oxide on silicon (CMOS) device, or an
electron-multiplying CCD (EMCCD). Under such circumstances, the
number of sensors (pixels) may reach tens or even hundreds of
thousands, or even millions.
At least some, and possibly all of the sensors may be suitable for
being inactivated, where appropriate, e.g. at the request of the
user.
In a particular embodiment the extent of the capture zone may be
modified without it being necessary to move the sensors over the
skin, e.g. by means of an optical system, such as a set of lenses,
for example. By way of example, an optical system made up of one or
more movable mirrors may serve to extend the field of view of the
skin, without moving the sensor(s).
Printer System
Any deposition technology can be used for the printer system.
Mention can be made in particular of offset printing, photogravure,
flexography, silk-screen printing, pad printing, electrophotography
(also known as xerography, electrostatic printing, or laser
printing), thermal printing (including in particular simple thermal
printing, thermal transfer printing, or thermal sublimation
printing), elcography, toner jet, magnetography, ionography (also
known as ion jet, electron beam imaging, or electrography), and ink
jet printing (including in particular so-called "continuous ink
jet" and "drop on demand" technologies).
Ink can be ejected as a jet or as droplets by a piezoelectric
element, by a thermal element (bubble jet), by hot-melting, or by
means of a valve (valve jet).
Mention may also be made of impact printing techniques, such as for
example hammer or chain printing, needle or dot matrix printing,
daisy wheel printing, thimble printing, and techniques such as
minispray, gas printing, compressed air printing, liquefied gas
printing, fluidized pressure printing, such as for example
airbrushes or minisprays obtained by a moving part, e.g. a moving
piezoelectric crystal.
The invention is better performed with contactless printing
techniques, and in particular ink jet printing technologies and
minispray techniques.
It is also possible to use printer means comprising a movable print
element such as a sponge, a felt, a paint brush, a hollow tube, or
a syringe, that contains ink that is put into contact with the skin
for printing purposes. Contact time may be adjustable and may vary
for example over the range 1/1000th of a second (s) to several
seconds.
The term "printing" is used to mean delivering a composition onto
the surface of the material for treatment, and in particular the
skin. In the meaning of the invention, printing relates to
delivering the composition onto or beneath the surface for
treatment. Thus, printer means using needle printing technology can
enable the ink to penetrate into the stratum corneum, the
epidermis, or the dermis. For this purpose, it is possible to use
strong needles or brittle needles, or the like.
The printer means may have a single print nozzle or a plurality of
nozzles in parallel. The printer system may have nozzles that are
dedicated to respective inks, or in a variant it may have a single
nozzle for ejecting a plurality of different inks in succession or
mixed together while printing is taking place so as to create the
color that is to be printed.
The printer means may be spaced apart from the skin so as to avoid
coming directly into contact with the skin. This spacing may be
fixed or adjustable. It is possible to adjust the spacing either
directly, e.g. by turning a knob or by acting on an adjustment
button that controls the movement of a motor, or else
automatically. For automatic adjustment, the processor unit
controls a motor to change the spacing.
If it is desired to perform sharp printing, the spacing can be
adjusted to a small value, e.g. one millimeter or less, and
conversely, if it is desired to perform fuzzier printing it is
possible to adjust the spacing to a greater distance, e.g. 1 cm or
more.
The printer means may include a print head capable of printing over
the entire surface for treatment. By way of example, the print head
may include one or more ink ejection nozzles. Assuming that the
user moves the device along an axis X, the print head may point
perpendicularly to the travel direction X of the apparatus, for
example.
The print head may be stationary within the device or it may be
movable along an axis Y that is perpendicular to the axis X. For
example, the device may perform Y-direction scanning of the print
head, with or without printing, while the carriage is returning.
The carriage may be driven by stepper motors, e.g. motors that are
addressed directly via a USB port.
When the handpiece has a plurality of print heads that are not
movable within the handpiece, the print heads may optionally be in
alignment, e.g. they may be disposed in a staggered
configuration.
The handpiece may include printer means that comprise at least one
print head capable of moving relative to the above-mentioned
carriage, along an axis Z that is perpendicular to the axes X and
Y.
The print head may be actuated mechanically during printing, e.g.
by a vibrator, so as to obtain a fuzzy effect. By way of example,
FIG. 3 is a diagram of a vibrator 58 incorporated in the handpiece
80. Vibration may be directed parallel to the region for
treatment.
The handpiece may include a vacuum or blower system for
accelerating drying and/or a heater system.
When the ink deposited on the keratinous material requires exposure
to light radiation, e.g. to ultraviolet (UV) light, in order to be
polymerized, then the handpiece may include a corresponding
lighting for assisting the polymerization of the ink(s)
concerned.
The printer means may comprise a print line made up of a plurality
of print elements disposed along a print line. The print elements
may for example be nozzles that enable the color that is to be
printed locally to be obtained on printing.
Printing may be performed by depositing a plurality of inks of
different colors in juxtaposed manner or in at least partial
superposition. The dots of different inks that are deposited may
optionally be of the same size.
The surface of the skin may be covered completely by the ink(s) or
gaps may be left between deposits of ink. Inks may be applied to
the skin like a silk screen.
The image printed on the skin need not be uniform, i.e. printing
may involve at least one ink being deposited in non-uniform manner
over the surface for treatment.
The application may also be performed by applying a composition
having a selected color contained in a reservoir of the device. The
color of this composition may result from the mixing of two or more
components.
The application system may apply a composition obtained by mixing
of components of different colors outside the device.
For example, the handpiece may send data to a mixing unit. The
mixing unit may mix two or more components to obtain a mixture
having the desired color. In some embodiments, the user may use an
independent mixing unit, that is configured to mix at least two
components to produce a mixture having the desired color. The
mixing unit may be used at, e.g., home, a point of sale, or at any
suitable location.
In other embodiments, the handpiece may send data relating to the
measured color to a decision unit. The decision unit may be located
remotely and may be configured to identify, e.g., from a library of
products, a product having the desired color.
In other embodiments, the user uses a decision unit. The decision
unit is capable to identify, e.g., in a library, a product having
the desired color. The mixing unit may be used, e.g., at home, at a
point of sale, or at any suitable location.
The device may include a monitor system enabling the user or the
device to determine whether printing is satisfactory or whether
printing needs to be continued or corrected. By way of example, the
monitor system uses the acquisition system or includes a camera or
a color detector that is specific thereto. For example, the device
may forward to a screen an image of the skin that is being treated.
Although hidden by the device, the skin appears to be visible to
the user, thereby enabling the user to assess the result while
printing is taking place.
Printing may be performed while the handpiece is stationary
relative to the skin.
When printing is performed with the handpiece moving over the skin,
since the movement of the handpiece is not necessarily rectilinear,
provision may be made for processing to be performed on a
point-to-point basis rather than on a line-to-line basis, so that
printing takes place in the identified position relative to the
skin even if the path followed by the handpiece is curved.
Inks
The device may print a deposit that is made up of one or more
cosmetic inks.
The inks are adapted firstly to the printing technology and
secondly to the color that is desired.
The inks used are preferably fluid and may be based on water or
organic solvents and may include at least coloring agents selected
from natural or artificial dyes, possibly fluorescent or
phosphorescent, organic and/or inorganic pigments, and mixtures
thereof.
The ink may include one or more non-colored materials that provide
optical effects, e.g. a fuzzy effect.
Where appropriate, one of the printed compositions may be a base
coat or a top coat in order to improve retention of the inks, for
example.
The coloring agent(s) and the optically active colorless agent(s)
may be in a dispersion, dissolved, or in an emulsion. They may also
form a mixture that is not very stable, that needs to be remixed or
redispersed at the time of use.
By way of example, the inks may be contained in a cartridge or a
group of cartridges that is easy to remove and replace.
One or more color ink cartridges may be used, e.g. corresponding to
primary colors (cyan, magenta, yellow, and black) or to colors that
are close to skin color (pink, ochre, beige, ivory, brown, . . .
).
In an implementation of the invention, a single printer nozzle is
used with a plurality of ink cartridges of predefined colors. For
example it is possible to use 1 to 1,000 e.g. sixteen colored inks,
representing a set of colors that are usually to be found on the
skin: pale beige, yellowish beige, pinkish beige, . . . . All of
the cartridges are connected to the printer nozzle, and the device
modulates the rate at which each of the cartridges delivers ink to
the printer nozzle as a function of the color to be printed, e.g.
using electrostatic microfluidic technology.
Processor Unit
The processor unit 30 may comprise a microcomputer, a minicomputer,
a microcontroller, or any other electronic system, e.g. a
programmable logic array.
The calculation performed on the basis of the measured values may
be calculating an average value.
The weights of each of the captured colors in the calculation of
the average may be equivalent, or they may differ, for example it
is possible to privilege color capture of one color more than
another, e.g. because one of the captured colors appears to be more
attractive or closer to that which is expected of the skin. The
processor unit may also seek to give precedence to one of the
captured colors. The user may place the sensors at a location where
it is preferable to give precedence to one of the color sensors,
e.g. close to margins such as the edges of the face.
Other averaging calculations may be performed.
By way of example, if three sensors provide three red values R1,
R2, R3, then the average for the red component is (R1+R2+R3)/3.
As explained above, it is also possible to consider that the
weights of the various sensors differ, so that the component of the
intermediate color is given for example by
R.sub.intermediate=(aR1+bR2+cR3)/(a+b+c). , b, and c may be
functions or constants, for example functions that depend on
lightness.
It may also be considered that the result is obtained in random
manner and lies within a range determined by extreme values, thus
making it possible to obtain results that are more natural. Thus,
from one printout to another, the printer unit may introduce a
random contribution in its calculations. Another approach consists
in generating color components in random manner. Nevertheless, it
is preferred for the calculations to ensure that the final result
lies within the ambit determined by the capture values.
Processing may be made more complex in order to improve the
result.
Thus, it is possible to take the average of the color components
and apply mathematical processing thereto, such as for example
shifting one or more color components or eliminating or correcting
results that lie outside tolerance zones. For this purpose, the
processor unit may be provided with data concerning tolerance
zones. When the processing results lie outside a tolerance zone,
the processor unit may either warn the user about this situation
without preventing printing, or else it may prevent printing.
It is also possible to apply mathematical processing to the
captured colors, e.g. prior processing consisting in eliminating or
correcting values that are considered outliers, and then calculate
the average after such prior processing.
One or more conversion tables may be used for calibration purposes,
since some color values may be modified in order to improve the
accuracy of rendering. Calibration conversion tables form the link
between theoretical colors and colors as measured.
The conversion tables may also serve to create color transformation
effects and they may be appropriate when the modification function
is not simple and is not uniform depending on the colors under
consideration.
The conversion tables may not only be addressable, they may also be
modifiable, loadable or downloadable, and based for example in the
memory of the processor unit.
Calculations may be performed amongst a plurality of averages so as
to limit risks, e.g. the risk of one printout being clearly
different from the preceding printout. Such smoothing may be based
on calculations in which earlier averages are involved in addition
to current color captures. Thus, on each new calculation, the
processor unit may average the calculation with the average of a
plurality of earlier calculations, e.g. the eight most recent
calculations. The weights given to the earlier averages compared
with the current color captures may be varied.
The apparatus may put printing on hold until the captured colors
have stabilized. Color capture may be repeated so long as the
values vary. It is only once the values have stabilized that
printing is launched. If a sensor value does not stabilize, then
the color value corresponding to the sensor may be ignored.
Proposed Example
FIG. 7 shows an embodiment example in greater detail.
In this example, the device has three color sensors 100.
The three color sensors are positioned in a triangle and spaced
apart from one another by a distance of 4 cm, for example.
Each color sensor contains three LEDs, a first delivering red light
(KP 2012SRD from the supplier Kingbright), a second delivering
green light (KP 201MGC from the supplier Kingbright), and a third
delivering blue light (KP 201PBC from the supplier Kingbright). As
a result, the device contains a total of nine LEDs.
In addition to the three LEDs, each color sensor includes a
photodetector 105, e.g. of reference C30807 from the supplier
Perkin Elmer. In all, the device contains three photodetectors
respectively referenced P1, P2, and P3.
Each color sensor may be positioned on the skin while being
protected from ambient light.
The three LEDs are positioned so that they illuminate by delivering
light towards the center and the photodetector receives light from
skin as illuminated in this way.
The device causes the first LED R to be switched on, the light
obtained by reflection from the skin to be captured, then the
second LED R to be switched on, and so on until a third capture has
been performed. The processor unit takes a first average of the
three capture values. The device then performs the same operation
for the three LEDs G and then for the three LEDs B. This sequence
may be performed at a rate lying for example in the range 10 Hz to
1000 Hz, e.g. 100 Hz.
Optionally, the device contains at least one contact detector, e.g.
that operates by measuring electrical resistance. The contact
detector(s) is/are connected to the processor unit.
Signals from the photodetectors are converted into digital form by
an analog-to-digital converter 110, e.g. a 6-input AD7794 from the
supplier Analog Device, which converter incorporates a 6-input
analog multiplexer, with use being made in this example of three of
those inputs, and of an output.
The converter 110 receives the signals from the three
photoreceivers 105 in sequential manner. Since each photoreceiver
is activated three times, when each of the three color diodes with
which it is associated is switched on, the converter receives a
total of 9 signals that it converts into respective digital signals
on 16 bits. The converter is connected to the processor unit, e.g.
via a serial link 106 of the serial peripheral interface (SPI)
type.
The processor unit 30 includes a programmable logic array, e.g. a
Cyclone III EPC 3 from the supplier Altera, clocked by an
oscillator 111 at a frequency of 24 megahertz (MHz), for
example.
The processor unit is programmed to operate the diodes and the
digital sensors at a rate of 100 Hz for example, as mentioned
above.
The program that controls the action of the processor unit 30 is
contained in a memory 115 of the EPROM type, e.g. an EPCS16 from
the supplier Altera, and data is transferred from this memory to
the unit 30 when it is switched on.
The device is provided with a button 160 for activating printing.
This start/stop button is connected to the processor unit 30.
The processor unit 30 performs the following functions:
1) sequentially switching on the nine lighting LEDs. The sequence
consists in switching on initially the three red diodes, one after
another, then the three green diodes, one after another, and
finally the three blue diodes, one after another;
2) controlling the converter 110 that is connected to the
photodetectors 105;
3) managing digital capture from the converter 110 as received over
the serial link 106;
4) performing calculation, which in the present example comprises
taking three averages of three digital captures, i.e. the average
of the three red captures, the average of the three green captures,
and the average of the three blue captures, with each of the
averages being encoded on 16 bits, for example;
5) performing 16-bit to 8-bit conversion on the three averages;
6) making a bitmap file made up of a plurality of portions, namely
an "Infoheader" portion, a "color table" portion, an RGB color
table, and an "image code" portion. The image code portion is
organized as a succession of three average color values on 8 bits
of the type: RGBRGBRGB . . . , each RGB group representing the
printing of one pixel. The number of repeats corresponds to the
number of pixels to be printed and is specified in the "Infoheader"
portion. This number of pixels is programmable and the larger this
number the greater the volume of ink that is deposited on the skin,
and so the more the deposit will be visible. The "Infoheader"
portion contains information concerning the lengths of the lines
and the numbers of lines that are to be printed. Insofar as the
device does not need such information, the processor unit may put
standard numbers in this portion, which numbers are not used;
and
7) indicating the state of the device and managing the user
interface; the apparatus may inform the user that capture has been
finished, that the averages have been taken, and that it is ready
for printing. An LED 161, e.g. a green LED, may indicate that
printing is ready to be triggered. A red LED 162 may indicate that
an abnormal value has been detected and that printing should not be
launched. The apparatus need not wait for instructions from the
user and may launch printing without waiting.
In this example, the "print head" portion of a USB-interface jet
printer is used, e.g. a printer sold under the trademark HP, Epson,
or Lexmark. The printer shell is removed. The print head portion is
extracted from its carriage while taking care to retain the
connection between said print head and the printer electronics 157.
It is also ensured that the ink cartridges are properly connected
to the print head, given reference 150 in FIG. 7. Cosmetically
acceptable inks are used.
The print head is placed relative to the color sensors so that the
output from the head delivers ink towards the middle of the
triangle formed by the three color sensors.
The print head is controlled, e.g. over a USB type wire connection
158, by a microcontroller 155, e.g. a CYZC68013 from the supplier
Cypress, used in master mode. The microcontroller is clocked at 24
MHz for example using the same oscillator 111 as is used for the
logic array 30.
The controller 155 is connected to the processor unit, e.g. via a
parallel connection.
Operation
Color capture is triggered immediately the three sensors are
pressed against the skin. In the present example, this means that
the device does not wait for the user to actuate the print button
in order to begin color capture.
The handpiece may be positioned on the skin in a zone that it is
desired to make more uniform. It is possible to position the device
and launch its action. Thus, in a few seconds, all of the
operations are performed and the skin is covered in an ink that
makes its tone uniform at a local level. This mode of use is
particularly suitable when the correction zones are small, e.g.
small color blemishes occupying a few millimeters, small scars, and
small visible veins.
At the time of printing, it is also possible to move the handpiece
a few millimeters. The advantage is to spread out the printing zone
so as to treat larger-area zones.
The processor unit generates a bitmap file that the printer system
knows how to interpret.
If intense printing is desired, the bitmap file is made up of a
large number of dots for printing. The larger the number of dots
printed by the print head, the greater the volume of ink that is
delivered.
If medium printing is desired, then the bitmap file is made up of a
smaller number of dots for printing. Where appropriate, the
processor unit may diminish color component values, e.g. divide the
three RGB components by a factor of 8 so as to make a bitmap file
having a larger number of dots for printing.
If transparent printing is desired, then the color component values
can be divided and a small number of dots printed.
The processor unit may generate other image files, in particular
compressed files using the Jpeg and other standards. The processor
unit may be provided with a conversion table that it keeps in
memory, e.g. in the memory of the processor unit 30. This
conversion table may have two portions, namely an "input" portion
with RGB values as read by the apparatus, and an "output" portion
with converted RGB values. This conversion table, which may be
specific to each device, may be made by calibration when the
apparatus is fabricated.
Regularly, the user may calibrate the device by acting as follows.
A test is performed on a portion of the body, e.g. the front face
of an arm. Three printed marks are made in this way. After
printing, the apparatus is repositioned so that the color sensors
are positioned over the three printed marks. The color sensors then
measure the color as printed, with the processor unit taking the
average and comparing this average with the averages obtained
beforehand. The processor unit may then modify the conversion
table.
It is possible to act on the print zone by enabling the print head
to move towards or away from the skin, either directly or under
motor control. Thus, by moving the print head away, a larger
printed mark is obtained. The processor unit may be programmed to
take this distance into account. If a larger distance is selected
between the skin and the print head, then the processor unit may
lengthen the printing sequence and increase the number of RGB
sequences in the bitmap file to compensate for the fact that the
size of the printed mark is greater.
A special function may serve to inactivate one or two sensors,
since the user may desire to rely on only two sensors or on only
one. This function may also be useful when the apparatus is used on
a zone of the body that does not enable the three sensors to be
made to engage the skin, e.g. a curved zone.
The invention is not limited to the examples described.
The device may be provided with buttons or other adjustment means
enabling at least one and possibly all three color components, e.g.
red, green, or blue, to be addressed, or else enabling one or the
other or a combination of these components to be increased or
decreased prior to printing. These buttons for increasing or
decreasing color components may be connected to the processor unit
that takes charge of making the corrections and that is capable of
storing them in memory.
As mentioned above, the handpiece may be provided with a vibrator
or a mechanical movement system that serves at the time of printing
to cause the print head to move so as to spread out the printed
zone without the user needing to move the handpiece over the skin.
It is possible to use a vibrator of the kind that is used in cell
phones.
The term "comprising a" should be understood as being synchronous
with "comprising at least one".
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References